ProcessingInstructions i.e. are ignored and dropped by default, for backwards compatibility.
If you want to include processing instructions set the parseProcessingInstructions flag to true before calling parse().

var domjs = new DomJS();
domjs.parseProcessingInstructions = true;

The first|root Element will contain an array called processingInstructions if the input document has any, otherwise processingInstructions is undefined.
Output of each processing instruction is always on a newline even if whitespace is different in the input document.

Sax strict parsing is on by default, and can be turned off by setting the strict flag.

var domjs = new DomJS();
domjs.strict = false;

An instance of DomJS should only be used once, but if you must reuse, call reset() before re-calling parse().
reset() does NOT reset the strict or processingInstructions flags.